# Artemis II

Artemis II is a scheduled mission of the NASA-led Artemis program. It will use the second launch of the Space Launch System (SLS) rocket and include the first crewed mission of the Orion spacecraft. The mission is scheduled to take place no earlier than April 2026. Four astronauts will perform a flyby of the Moon and return to Earth, becoming the first crew to travel beyond low Earth orbit since Apollo 17 in 1972. Artemis II will be the first crewed launch from Launch Complex 39B of the Kennedy Space Center since STS-116 in 2006.
The launch was originally designated Exploration Mission-2 (EM-2) when the mission was intended to collect samples from a captured asteroid in lunar orbit by the now-cancelled robotic Asteroid Redirect Mission; it was renamed after the introduction of the Artemis program.

## History
### Mission planning and launcher selection (2017–2021)

In 2017, Exploration Mission-2 was a projected single-launch mission of a Space Launch System (SLS) Block 1B rocket with an Exploration Upper Stage, lunar Block 1 Orion spacecraft, and a payload insertion of 50.7 tonnes (55.9 short tons; 112,000 lb). The plan was to rendezvous with an asteroid previously placed in lunar orbit by the robotic Asteroid Redirect Mission and have astronauts perform space-walks and gather samples. After the cancellation in April 2017 of the Asteroid Redirect Mission, an 8-day mission was proposed with a crew of four astronauts, sent on a free-return trajectory around the Moon. Another proposal suggested in 2017 was to take four astronauts aboard Orion on an 8-to-21–day trip around the Moon to deliver the first element of the Deep Space Gateway. In March 2018, it was decided to launch the first Gateway module on a commercial launch vehicle because of delays in building the Mobile Launcher needed to hold the more powerful Exploration Upper Stage. The launcher was selected to be the SpaceX Falcon Heavy.
NASA's CubeSat Launch Initiative (CSLI) sought proposals in 2019 from U.S. institutions and U.S. companies to fly their CubeSat missions as secondary payloads aboard the SLS on the Artemis II mission. NASA would accept proposals for both 6-unit (12 kg, 26 lb) and 12-unit (20 kg, 44 lb) CubeSats. As with the Artemis I mission, the CubeSats flying on Artemis II were to be mounted on the inside of the stage adapter ring between the SLS upper stage and the Orion spacecraft, and will be deployed after Orion separates. Selections were initially planned to be made by February 2020, but in October 2021, NASA dropped all secondary payloads from the mission.

### Hardware development, testing and integration (2021–present)

On 11 February 2023, NASA flipped the engine section for the Artemis II core to horizontal, the final major milestone before mating the section to the rest of the vehicle. On 20 March, the engine section was mated with the Artemis II core stage in Building 103 at the Michoud Assembly Facility in New Orleans. NASA expected the core stage, complete with engines, to be delivered to the Kennedy Space Center in summer 2023. In May, the delivery date was moved to late fall 2023. The RS-25 engines with serial numbers E2047, E2059, E2062, and E2063 were installed on the core stage in New Orleans by 25 September 2023. Finally in June 2024, NASA announced the planned delivery of the fully outfitted core stage to KSC in July 2024, which was successfully carried out from the 16th to the 25th. The adapters needed for integration of the full vehicle also reached substantial completion in June 2024, and arrived at Kennedy Space Center in September 2024.
The crew was announced on 3 April 2023, as stated by NASA Administrator Bill Nelson, in his "State of NASA" speech reacting to President Joe Biden's FY2024 budget proposal. The announcement occurred at a NASA facility at Ellington Field outside Houston. They appeared later that day at nearby NRG Stadium for the 2023 March Madness championship game.
NASA had originally planned to begin rocket stacking operations in September 2024. However, the process was delayed by over two months as the agency investigated issues with Orion's life support system and greater than expected damage to Orion's heat shield observed after the Artemis I reentry. Rocket stacking finally began on 20 November 2024.

### Launch date

During preliminary reviews in 2011, the launch date was placed somewhere between 2019 and 2021, but afterwards the launch date was delayed to 2023. In January 2024, the mission was expected to launch no earlier than September 2025. However, in October 2024, the NASA Office of Inspector General determined that the Exploration Ground Systems team had already used up their time reserved for resolving any unforeseen issues, leading the office to determine that the September 2025 launch date would likely be delayed. In December 2024, outgoing Administrator Nelson announced that the launch was delayed due to the months of engineering investigations into issues with the life support system and heat shield, but should occur no later than April 2026.

## Crew

Prime crew :
| Position | Astronaut | Astronaut |
| Commander | Reid Wiseman, NASA Second spaceflight | Reid Wiseman, NASA Second spaceflight |
| Pilot | Victor Glover, NASA Second spaceflight | Victor Glover, NASA Second spaceflight |
| Mission Specialist 1 | Christina Koch, NASA Second spaceflight | Christina Koch, NASA Second spaceflight |
| Mission Specialist 2 | Jeremy Hansen, CSA First spaceflight | Jeremy Hansen, CSA First spaceflight |
Backup crew :
| Position | Astronaut | Astronaut |
| Commander / Pilot / Mission Specialist | Andre Douglas, NASA | Andre Douglas, NASA |
| Mission Specialist | Jenni Gibbons, CSA | Jenni Gibbons, CSA |
Artemis II is to be crewed by four astronauts: Commander Reid Wiseman, Pilot Victor Glover along with Mission Specialists Christina Koch and Jeremy Hansen. On 22 November 2023, Jenni Gibbons was announced as Hansen's backup. On 3 July 2024, Andre Douglas was announced as the backup for the three NASA astronauts.
Glover, Koch, and Hansen are to be the first person of color, woman, and non-American to go beyond low Earth orbit respectively. Hansen and Gibbons are Canadian and have been assigned by the Canadian Space Agency; a 2020 treaty between the United States and Canada led to their involvement.

## Mission

The Artemis II mission plan is to send four astronauts in the first crewed Orion spacecraft into a lunar flyby using the Block 1 variant of the Space Launch System. The mission profile is a multi-trans-lunar injection (MTLI), or multiple departure burns, and includes a free-return trajectory from the Moon. The Orion spacecraft will be sent to a high Earth orbit with a period of roughly 24 hours. During this time the crew will perform various checkouts of the spacecraft's life support systems as well as an in-space rendezvous and proximity operations demonstration using the spent Interim Cryogenic Propulsion Stage (ICPS) as a target. When Orion reaches perigee once again, it will fire its main engine to complete the TLI maneuver, which will send it to a lunar free-return trajectory, before returning to Earth.

### Optical communications

Artemis II will test and demonstrate optical communications to and from Earth using the Orion Artemis II Optical Communications System (O2O). The O2O hardware will be integrated into the Orion spacecraft and includes an optical module (a 4-inch [100 mm] telescope and two gimbals), modem and control electronics. O2O will communicate with ground stations in California and New Mexico. The test device will send data to Earth with a downlink rate of up to 260 megabits per second.

### Mission overview

Artemis II's trajectory can be divided into several key phases:

#### Launch

* Vehicle: Space Launch System (SLS) Block 1
* Launch Site: Kennedy Space Center, Launch Complex 39B
* Duration: Approximately 8 minutes to reach initial orbit
* Trajectory: The SLS will launch Orion into a low Earth orbit (LEO) for a very short period of time, then fire again to place Orion in a highly-eccentric orbit with a period of about 24 hours.

#### Earth orbit and systems checkout

* Orbit: Highly-eccentric orbit with an apogee above that of typical communications satellites
* Duration: About 24 hours
* Activities: The crew will perform checks on the Orion spacecraft’s systems, ensuring all are functioning correctly before proceeding with the mission. They will also demonstrate proximity operations with the upper stage of their launch vehicle.

#### Translunar injection

* Maneuver: After the systems checkout, the Orion spacecraft will perform a TLI burn using its Service Module, propelling it out of Earth orbit towards the Moon.
* Trajectory: A precise burn to place Orion on a trajectory that will take it around the Moon.

#### Lunar flyby

* Altitude: Closest approach approximately 7,400 kilometers (4,600 mi) from the lunar surface.
* Duration: Several days to travel to the Moon, fly around it, and begin the return trip.
* Activities: The crew will continue to monitor and test Orion’s systems and gather data on deep space travel effects.

#### Return trajectory

* Maneuver: After the lunar flyby, Orion will use the Moon’s gravity to assist in its return to Earth, a maneuver known as a free-return trajectory.
* Trajectory: A path that will naturally bring Orion back to Earth without the need for additional propulsion if systems fail.

#### Re-entry and splashdown

* Re-entry Phase: Orion will re-enter Earth's atmosphere.
* Splashdown: In the Pacific Ocean, recovery teams will retrieve the spacecraft and crew.
* Duration: The entire mission is expected to last about 10 days.

## Similar missions

In December 1968, the Apollo 8 mission, crewed by astronauts Frank Borman, Jim Lovell, and William Anders, flew their command and service module beyond low Earth orbit and completed ten orbits of the Moon. Similar to the planned Artemis II mission in that it was crewed and did not land, it differed by being placed into orbit. Apollo 13 (1970) was the only Apollo mission, and only crewed spaceflight to date, that flew past the Moon by a free-return trajectory.